import calendar
def get_date(year):
    list = []
    for i in range(1,13):
        m = calendar.monthrange(year,i)
        start = '{}-{}-01,'.format(str(year),str(i).zfill(2))
        end ='{}-{}-{}'.format(str(year),str(i).zfill(2),m[1])
        arrangement = start+end
        list.append(arrangement)
    print(list)
get_date(2020)